initialize data of state variables also in case of no term caches
initialize data of state variables also in case of no term caches

- this fixes linear elastic curve in examples/compare_elastic_materials.py

rc/sfepy,vlukes/sfepy,RexFuzzle/sfepy,olivierverdier/sfepy,BubuLK/sfepy,sfepy/sfepy,lokik/sfepy,vlukes/sfepy,lokik/sfepy,lokik/sfepy,sfepy/sfepy,RexFuzzle/sfepy,sfepy/sfepy,BubuLK/sfepy,rc/sfepy,BubuLK/sfepy,olivierverdier/sfepy,olivierverdier/sfepy,lokik/sfepy,rc/sfepy,vlukes/sfepy,RexFuzzle/sfepy,RexFuzzle/sfepy